On Wed, Sep 30, 2009 at 05:00:06PM +0200, ext Niels Roest wrote: > Hi Andres. > > I assume you mean DWOP_... and DWCAPS_ALPHACHANNEL. > > DWCAPS_ALPHACHANNEL will add an alpha channel to the window back buffer > upon creation. > example: if the layer, where you will create the window on, has default > RGB16, then using DWCAPS_ALPHACHANNEL will make the window instead have > ARGB. If the layer is already default alpha capable, e.g. LUT, or > ARGB4444, then the window will be created with this format. > > DWOP_ALPHACHANNEL will do the blitting operation with alpha blending. > Suppose you have a window with color 0,0,0,0 (black see-through) that > you blend onto a background with ff,ff,ff,ff (white opaque). If you do > NOT use DWOP_ALPHACHANNEL, the window will simply be copied resulting in > a "hole" in the background (the original background is gone, and black > instead if you have no layer behind). Using DWOP_ALPHACHANNEL will > result in no change, the white background is still visible. > > o, and DWOP_ALPHACHANNEL is not possible without DWCAPS_ALPHACHANNEL. > > You might need to "Flip" to see the effects. > > Greets > Niels
Thanks I assume then that if I actually explicitly specify the window's surface's format using DWDESC_PIXELFORMAT the DWCAPS_ALPHACHANNEL doesn't actually matter (assuming I make sure the format I pass is an alpha format). regards -- Qt Development Frameworks, Nokia, http://qt.nokia.com Anders Bakken _______________________________________________ directfb-dev mailing list directfb-dev@directfb.org http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-dev
